2003 Buick Rendezvous Owner's Manual - Page 180

(Bi-Level): This mode directs half of the air to the instrument panel outlets, then directs the remaining air to the floor outlets. Cooler air is directed to the upper outlets and warmer air to the floor outlets. (Floor): This mode directs most of the air to the floor outlets. Use this mode to send air to the rear of the vehicle. Keep the area under the front seats free of objects that could obstruct airflow to the rear of the vehicle. The right knob can also be used to select defog or defrost mode. For more information, see "'Defogging and Defrosting" later in this section. (Fan): Turn the left knob clockwise or counterclockwise to increase or decrease the fan speed. Turn the knob to OFF to turn off the fan. The fan must be turned on for the air conditioning compressor to operate. Press this button to turn the ouiside air [-